Hub which converts scada protocols to the BLUEJAYTM protocol

ABSTRACT

A wireless hub uses a first processor to communicate with IEDs, uses a second processor to communicate with landline SCADA devices, and uses a third processor to extract, store and exchange messages between SCADA protocols and IED data formats so as to as to permit two way communications between SCADA users and IEDs which are independent of protocol data formats and time of exchange.

[0001] This application is a continuation in part of application Ser.No. 10/405,558 titled A WIRELESS COMMUNICATIONS HUB WITH PROTOCOLCONVERSION filed for Robert W. Beckwith on Apr. 2, 2003 which was acontinuation in part of application Ser. No. 10/074,110 titled AWIRELESS COMMUNICATIONS HUB WITH PROTOCOL CONVERSION filed for Robert W.Beckwith on Feb. 11, 2002 which was a continuation in part ofapplication Ser. No. 09\479,650 titled “EXPANDED CAPABILITIES FORWIRELESS TWO-WAY PACKET COMMUNICATIONS FOR IEDs” filed by Robert W.Beckwith on Jan. 8, 2000 which claimed the priority date of provisionalpatent application Ser. No. 60/116,984 filed by Robert W. Beckwith onJan. 25, 1999 titled “RADIO AS THE MAN/MACHINE INTERFACE FOR AN IED”.The title has been changed.

REFERENCES

[0002] The IEEE 100 dictionary of IEEE standards terms, seventh editiondefines the following terms which are used herein:

[0003] 1. “intelligent electronic device (IED) Any device incorporatingone or more processors with the capability to receive or senddata/control from or to an external source.”

[0004] 2. “supervisory control (1) (supervisory control, dataacquisition, and automatic control) An arrangement for operator controland supervision of remotely located apparatus using multiplexingtechniques over a relatively small number of interconnecting channels.

[0005] A form of remote control of remotely located units by electricalmeans over one or more common interconnecting channels.”

[0006] Definition of words as used herein:

[0007] 1. “bit-stream”: any serial string of binary bits in timesequence.

[0008] 2. “message”: the bits within a bit-stream that have beenassigned a meaning.

[0009] 3. “data format”: the information required to code and decodemessages.

[0010] 4. “memory format” the information required to place data withinan electronic memory and to find data once placed in memory.

[0011] 5. “routing”: the bits within a bit stream that direct messagesin a bidirectional path between two points within a communicationsnetwork.

[0012] 6. “DSSS: Direct Sequence Spread Spectrum” The message signal inDSSS transmission is “spread” at baseband and then modulated to theoperating frequency (such as the ISM band from 2.4 GHz to 2.4835 GHZ asused by the Beckwith Electric Company M-2901 BLUEJAY™ wirelesstransmitter/receivers) . When received the signal is first demodulatedto the baseband frequencies and then “despread” to recover the message.

[0013] 7. “DSSS BBP: DSSS Base Band Processor” The Prism II DSSS BBPchip used in BLUEJAY™ products sends messages many times at frequenciesas high as 11 gigabits per seconds. Various signal failure avoidancetechniques are used in repeated transmissions to provide a very highprobability that the message components will be received error free eachmillisecond of message time flow. For that reason BLUEJAY™ products usea one megabit per second bit stream transmission rate. An efficientmessage routing data format ie protocol provides a BLUEJAY™ messagetransmission rate of 0.5 megabits per second.

[0014] 8. A “protocol” consists of a detailed method of combiningmessages and routings to form a bidirectional digital communicationspath between two points.

[0015] 9. “legacy IEDs” a properly operating IED which is not equippedto communicate in various present day SCADA protocols.

PRIOR ART

[0016] U.S. Pat. No. 5,621,727 by Vaudreuil is an example of networkmessaging systems using hubs. The Vaudreuil patent will be used hereinto describe the differences between the present inventive hub and thenetwork messaging systems of Vaudreuil.

[0017] Beckwith Electric Company (BECO) manufactures M-2901 BLUEJAY™wireless transmitter/receivers. BLUEJAY™ devices are used to providelicense free bidirectional wireless digital communications between twopoints. BLUEJAY™ devices make no attempt to avoid data crashes otherthan that described above under “definitions” as provided by IntersilPrism II chip sets used in the M-2901 devices. The M-2901 does notcomply with IEEE standard 802.11.

[0018] It has been demonstrated that BLUEJAY™ devices are capable oferror free communications with no interference with or by other wirelessproducts in general use in the Industrial, Scientific and Medical (ISM)band. This band is from 2.4 GHz to 2.4835 GHZ as set aside in the USAfor unlicensed use of DSSS technology.

[0019] Wireless BLUEJAY™ bit-streams flow at one megabit per secondrates. Continuous two way digital communications at 0.5 megabit persecond message rates is provided.

SUMMARY OF THE INVENTION

[0020] Unlike the hubs described in the Vandreuil patent referencedabove, the inventive hub disclosed herein is for the special purpose ofproviding SCADA communications to a human operator who has continuousresponsibility for the operation of installations such as electric powersubstations and generating plants. The SCADA communications may use ofany one of a variety of protocols in general use.

[0021] Wireless communications is provided to legacy IEDs withininstallations such as electric power substations and generating plantsby Beckwith Electric BLUEJAY™ wireless transmitter/receivers. Protocolconversion is provided between any protocol of an operators' choice tothe protocol of BLUEJAY™ wireless devices used to read information ineach IED memory format.

[0022] Messages are held for any required length of time by theinventive hub 115. Messages are exchanged between the hub 115 and theIEDs at rates and times as are fitting to the practical operation of theIEDs. These rates may be as high as 0.5 megabits per second.

[0023] Operator commands are communicated through the hub to anyselected IED within a few tenths of a second. Failure of an IED tocommunicate is taken as an IED failure and a failure report is generatedand sent to the operator.

[0024] The inventive hub uses one processor acting as a full computerfor message storage for each IED, for protocol conversion as requiredbetween the BLUEJAY™ wireless communications devices and SCADAcommunications devices and for time buffering of any length required bythe operator. For example, historic IED data for a month can be held ifrequired.

[0025] Two communications processors are provided, one for BLUEJAY™wireless communications with IEDs and a second for SCADA communicationswith an operator.

[0026] A user interface port is provided for IED data entry, hub programentry and maintenance communications with the three processors.

[0027] The foregoing features and advantages of the present inventionwill be apparent from the following more particular description of theinvention. The accompanying drawings, listed herein below, are useful inexplaining the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0028]FIG. 1 A block diagram of the inventive hub communicating with anIEDs and with a SCADA user.

[0029]FIG. 2 The connections of a hub user interface computer to thehub.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] The term “SCADA” (for Supervisory Control And Data Acquisition)is used herein to refer to practice as described in reference 2.

[0031] The term “IED” is used herein to refer to devices within electricutility substations or within industrial complexes which are underoperators control using SCADA practices. It is the BLUEJAY™ and only theBLUEJAY™ protocol that is used to communicate with IEDs by the inventivehub 115 of the present invention.

[0032] Remarks contained herein concerning BLUEJAY™ products andprotocols are for information only so as to serve as a limitation forthe hub 115 capability in communicating with legacy IEDs.

[0033]FIG. 1 shows a block diagram of the inventive hub 115. Dprocessors 130 run continuously using programs for managing data filesof information concerning each IED 103 served by hubs 115.

[0034] Processors P 120 have 32 bit busses 123, D 130 have 32 bit busses132 and S 140 have 32 bit busses 144. These are each partitioned withfirst 16 buss bits 0 through 15 used for parallel data transfer via TwoPosition Parallel Bus Connector (TPPBC) 125. Processors P 120 haveNon-Volatile Memory 129, D 130 have Non-Volatile Memory 131 and S 140have Non-Volatile Memory 143. These non-volatile memories are accessedby the associated processors using the second 16 buss bits 0 through 15.

[0035] Using the BLUEJAY™ protocol BECO model M-2910 BLUEJAY™ wirelesstransceivers 101 using antennae 102 communicate with typical IEDs 103.IEDs 103 communicate via BLUEJAY™ devices 100 having antennae 105.Devices 100 may be BECO model M-2910 or selectively may be other BECOBLUEJAY™ devices best suited for particular IEDs.

[0036] Clock signal generator 150 provides synchronous clock signals online 151 to processors P 120, on line 152 to processors D 130 and online 153 to processors S 140.

[0037] Wireless transceivers 101 communicate with P processors 120 viatwo way serial interconnection 104 and synchronous serial port 127. Pprocessors 120 exchange data with D processors 130 by parallel transferthrough two position parallel bus connectors 125. Data is sent to andreceived from IEDs using the BLUEJAY™ protocol.

[0038] P processors 120 buffer data for purposes of matching data speedswith wireless transceivers 101, for effecting parallel transfers of datawith D processors and if necessary to wait for SCADA communications toend. Direction of parallel transfers is established by enabling line 116for flow from processor P 120 to processor D 130. Enabling line 117establishes data transfer from D processor 130 to P processor 120. Oncea direction is enabled, transfer in the other direction is blocked.

[0039] S processors 140 provide communications for human operators ofelectric utility substations or industrial complexes using SCADApractice. Hub 115 provides SCADA communications over circuits 145connecting via dedicated interface circuits 141 to land line devicesused by the SCADA users.

[0040] Generally SCADA circuits use a dedicated communications networkconnected between more than one SCADA user.

[0041] Several SCADA protocols of common choice may be held in Sprocessor memory 143. If not, a SCADA protocol can be added by the hubuser via the hub user interface computer 200 as described under FIG. 2.

[0042] S processor 140 communicates via parallel bus connector 125 to Dprocessor 130. Connector 125 is two position and can connect S processor140 to D processor 130 or P processor 120 to D processor 130. Lines 118and 119 select the direction of communications between S processor 140and D processor 130 and operate by the first direction chosen blockingthe other direction. Line 136 enables communications between S 140 and D130 processors and line 121 enables communications between P 120 and D130 processors. Again operation is on the basis of the first pair ofprocessors enabled blocking the other. Processor S 140 does notcommunicate with processor P 120.

[0043] First 16 lines 0 through 15 on each of 32 bit parallel busses123, 132 and 144 are used for parallel communications via Two PositionParallel Bus Connectors 125. Second 16 lines 0 through 15 on each of 32bit parallel busses 123, 132 and 144 are used for memory management bythe respective processors P 120, D 130 and S 140.

[0044] Again, processors S provide buffering for matching SCADA devicedata rates, for providing parallel bus communications and if necessaryfor waiting for P 120 to D 130 communications to end.

[0045] Processors D 130 and S 140 use multitask programming. Theparallel data transfer is programmed in assembly language and takesplace well within the time of one task. Data crashes are avoided byalternating assignment of parallel data transfers to tasks of amultitask program.

[0046] Processor D 130 contains a first field of memory formatinformation for each IED served by hub 115. This information is thatrequired to convert messages from each IED to a generic form.Selectively this is a binary form identifying such things as:

[0047] 1. the IED,

[0048] 2. the data type, ie Volts, watts, current, VArs etc

[0049] 3. scaling factors

[0050] In addition processor D 130 contains a second field of convertedinformation from the generic form into the message format form used inthe S 140 processor as required by the SCADA protocol of choice.

[0051]FIG. 2 shows a user interface computer 200 using a program knownas “HUBCOM”. When needed, interface computer 200 can be interconnectedwith the hub 115 by use of cable 202. One end of cable 202 is insertedinto RS232 port 201 on computer 200 with the other end connected toRS232 port 203 on RS232 paralleling device 204 located within Hub 115.The RS232 paralleling device 204 connects to asynchronous port 210 on Pprocessor 120 via connection 205, to asynchronous port 209 on Dprocessor 130 via connection 207 and to asynchronous port 208 on Sprocessor 140 via connection 206.

[0052] The hub user will select and activate the SCADA program protocolof choice if contained in non-volatile memory 143 of the S processor140. If not available the hub user may enter a SCADA protocol of choice.

[0053] The hub user can enter memory format and set point informationfor each IED which in general is expected to differ one from another.

[0054] The hub user may read IED data stored in the D processor and maycommunicate with the IEDs in a manner imitating a SCADA user.

[0055] User interface computer 200 is also used for other maintenancechecking of hubs 115.

ADVANTAGES OF THE INVENTION

[0056] A. Provides SCADA communications to legacy IEDs served byBeckwith Electric BLUEJAY™ wireless devices.

[0057] B. Stores information including individual IED memory format andsetpoint settings as required for proper scaling of data.

[0058] C. Takes the cost of ethernet out of IEDs.

[0059] D. Eliminates costs of physical data handling lines withinsubstations and industrial plants.

[0060] E. Low cost as compared to competitive wired hubs.

[0061] While the invention has been particularly shown and describedwith reference to preferred embodiments thereof, it will be understoodby those skilled in the art that various changes in form and details maybe made therein without departing from the spirit and scope of theinvention.

1. A hub device providing communications between SCADA users havingprotocols of choice and legacy IEDs using BLUEJAY™ wireless protocolcomprising in combination: a) first processor means for using BLUEJAY™wireless transceivers for exchanging IED messages in legacy IED memoryformat with said hub, b) second processor means for exchanging SCADAuser messages in data format in bit streams using SCADA users protocolsof choice, c) third processor means in said hub for two way convertingmessages held in IED memory format and messages held in bit stream dataformats as required for said SCADA users protocols of choice, e) digitalcommunications means for two way communicating IED messages between saidfirst and said third processors, and f) digital communications means fortwo way communicating SCADA messages between said second and said thirdprocessors whereby SCADA users can communicate via a hub with legacyIEDs.
 2. A hub device as in claim 1 further comprising in combination:a) program means in said third processor for extracting messagescontained in said bit-streams and converting message formats in eitherdirection between that of IEDs and that of SCADA devices, and b) storagemeans in said third processor for storing messages for a selected timebefore sending in either direction through said hub wherebycommunications through said hub are not constrained by individualprotocols or by time of transmission or reception.
 3. A device as inclaim 1 wherein said program means for said third processor convertingsaid messages to a generic format for converting message formats as theyflow in either direction through said hub.
 4. A device as in claim 1wherein said third processor includes non-volatile memory.
 5. A deviceas in claim 1 further comprising in combination: a) non-volatile memorymeans for using with said first processor, b) synchronous serial portmeans for using with said non-volatile memory, c) connection meansbetween said synchronous serial port and said wireless transceiver meansfor exchanging digital bit-streams in either direction between said IEDsand said hub, and d) program means for said first processor forexchanging digital bit streams in either direction between said IEDs andsaid first processor of said hub.
 6. A device as in claim 1 furthercomprising in combination: a) program means in said third processor forconverting digital bit streams to SCADA protocol formats, b) programmeans in said first processor for exchanging said bit streams with saidsecond processor, c) program means in said second processor forexchanging said bit streams with said third processor, and d) programmeans in said second processor for exchanging said bit streams with saidSCADA users whereby SCADA users communicate with IEDs in eitherdirection and with selective time delays in communications.
 7. A deviceas in claim 1 for a single device means providing clock signals to saidfirst, second and third processors whereby said first, second and thirdprocessors operate in synchronism.
 8. A device as in claim 1 furthercomprising in combination: a) two position parallel bus connectiondevice means for selectively providing parallel communications betweensaid first and third processors or between said second and thirdprocessors, b) connection means for connecting said first processor anda first input of said two position parallel bus connection device, c)connection means for connecting said second processor and a second inputto said two position parallel bus connection device, d) connection meansfor connecting said third processor means and a common input to said twoposition parallel bus connection device, e) binary control connectionmeans for connecting between said first processors and said two positionparallel bus connection device, f) binary control connection means forconnecting between said second processor and said two position parallelbus connection device, g) program means for each said first and secondprocessors for switching the direction of said two position parallel busconnection device, and h) further program means for said third processorchoosing between communications with said first processor andcommunications with said second processor whereby digital bit streamsare exchanged at high speeds using parallel bus connections.
 9. A deviceas in claim 1 wherein said first processor communicates wirelessly withIEDs,
 10. A device as in claim 1 wherein said second processorcommunicates with selected SCADA devices using the protocol format ofsaid selected SCADA protocols.
 11. A device as in claim 1 for said thirdprocessor means storing messages, converting protocol formats andexchanging messages between IED devices and SCADA protocols.
 12. Adevice as in claim 1 further comprising in combination: a) computermeans for users communicating with said hub, b) RS232 port means forconnecting said user interface computer for communicating with said hub,c) paralleling device means for paralleling RS232 ports, d) RS232 portmeans for communicating with said paralleling device, e) connectionmeans for connecting said paralleling device to RS232 ports for use withsaid user interface computer, f) connecting means for connecting betweensaid paralleling device and asychronous ports of each of said first,second and third processors, and g) program means for said userinterface computer for entering required programs into each of saidfirst, second and third processors.
 13. Interface computer means as inclaim 12 for entering SCADA protocol programs into said second processorwhereby the choice of SCADA protocol is independent of the memory formatof any IED.
 14. Interface computer means as in claim 12 for enteringprograms for operation of said communications hub into said first,second and third processors.
 15. Interface computer means as in claim 12for users entering data as required for any specific IED.
 16. Interfacecomputer means as in claim 12 for users reading data related to anyspecific IED.
 17. A communications hub comprising in combination: a) afirst microprocessor means for processing bit-streams in eitherdirection using a plurality of first message protocol formats, b)digital port means for said first microprocessor exchanging bit-streamsin either direction with first outside sources, c) second microprocessormeans for processing bit-streams in either direction using a pluralityof second message protocols, d) digital port means for said secondmicroprocessor exchanging bit-streams in either direction with secondoutside sources, e) third microprocessor means for storing, convertingmessage protocols and exchanging digital bit-streams in either directionwith said first microprocessor for communications with said firstoutside sources, and f) said third microprocessors also having means forstoring, converting message protocol formats and exchanging digitalbit-streams in either direction with said second microprocessor forcommunications with said second outside sources.
 18. A method ofproviding communications between IEDs and land line devices, said methodcomprising the steps of: a) providing a communications hub havingmultiple digital processors for processing bit-streams flowing betweenSCADA devices and IEDs, b) connecting bit-streams flowing between afirst of said processors in the format of said IEDs, c) connectingbit-streams flowing between a SCADA device and a second of saidprocessors in the format of said SCADA device, d) selectively switchingfrom communicating between said first and a third of said processors andcommunicating between said second and said third processor, e) in saidthird processor, converting messages in the memory format of said IEDs,as contained in bit-streams flowing between said IEDs and said hub, intoa generic format, f) in said third processor, converting messages in thedata format of said SCADA protocols as contained in bit-streams flowingbetween said land line devices and said hub, into a generic format, g)in said third processor, using generic formats for converting messagesin either direction between IED memory formats and SCADA protocolformats, and h) storing said converted messages in said third processorsfor subsequent transmission, whereby communications through said hub arenot constrained by individual protocol formats or by time oftransmission or reception.
 19. A method as in claim 18 further includingthe steps of: a) connecting an interface computer in parallel toasynchronous ports in each of said three processors, and b) providinginputs through said interface computer to activate selected programs insaid three processors, and to enter and receive selected data to andfrom said processors.
 20. A method as in claim 18 including thefollowing steps: a) communicating between said first and thirdprocessors using bus to bus parallel transferring of data, b)communicating between said second and third processors using bus to busparallel transferring of data, c) using first pairs of control linesdefinable as A and B for enabling communications between said first andthird processors, d) using second pairs of control lines definable as Cand D for enabling communications between said second and thirdprocessors, and e) selectively enabling only one of said pairs ofcontrol lines during a given time and inhibiting the other of said pairswhereby data crashes of data flowing in either of two directions throughsaid hub are avoided.